Adjustable buckle for a respriator mask

ABSTRACT

An adjustable buckle located around a resilience strap for a respirator including a resilient strap material having a particular length, width and thickness. An adjustable buckle is molded around the strap at a particular position and formed of two interlocking members each located at an end position of the strap and having at least one portion that interlocks with a corresponding portion of the other member. This provide for locking and unlocking of the members with each other. At least one of the interlocking members includes a plurality of such portions that interlocks with the corresponding portion of the other member. The plurality of portions are spaced from each other along the length of the strap so that an individual one of the plurality of portions may be interlocked with the corresponding portion of the other member to adjust the length of the strap.

BACKGROUND OF THE INVENTION

The present invention relates to an adjustable buckle of the type that can be used with a respirator mask and specifically relates to adjustable buckle members that are integrally molded on a strap on a continuous basis.

Adjustable buckles are used as part of a respirator mask to allow the user of the mask to put the mask on and take the mask off in an easy fashion and to adjust the length of the strap for comfort. Part of the difficulty with prior art adjustable buckles is that they are somewhat cumbersome in structure and thereby expensive to manufacture. The present invention relates to an adjustable buckle that is simple in construction and easy to manufacture.

SUMMARY OF THE INVENTION

In the adjustable buckle of the present invention, the adjustable buckle is formed by two buckle members one of which has multiple elements molded around an elastic band and locked in position onto the elastic band using a novel method of manufacture described in prior U.S. Pat. No. 5,970,585. Specifically, if an adjustable buckle member is merely molded around an elastic band, when the molding process is over and the adjustable buckle member cools, the elastic band would slip within a molded channel formed in the molded adjustable buckle member. This is because the elastic material when stretched tends to reduce in size thereby allowing for slippage of the band inside the adjustable buckle member.

The prior invention overcomes this problem by pre-stretching the elastic band prior to the molding of the adjustable buckle members around the elastic band. The adjustable buckle members are actually molded around the elastic band in the stretched condition so that the elastic band within the channel in the molded member is actually stretched to a smaller size. When the molded adjustable buckle members cool, the band portion is already stretched and locked by friction in position within the channel. The stretched band wants to return to its unstretched state and this tends to increase the friction. Further pulling on the elastic band does not produce any significant further stretching of the band within the adjustable buckle members. The adjustable buckle member therefore is held tightly onto the elastic band by friction during use and the elastic band cannot slip out of the adjustable buckle. The present application is an improvement over the prior invention in providing for a simple means of adjustment of the length of the strap to which the buckles are attached by multiplying the number of buckle elements of one or both of the buckle members so that different length straps can be formed by interconnecting different buckle elements.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a user of a respiratory mask and showing the adjustable buckles of the present invention at the back of the mask;

FIG. 2 is a detailed perspective view of two buckle members one of which includes multiple elements to form the adjustable buckle of the present invention;

FIG. 3 illustrates the buckle members one with multiple elements formed on an elastic band before the adjustable buckle members are separated;

FIG. 4 is a cross-sectional view taken along lines 4-4 of FIG. 3, and

FIG. 5 illustrates an alternate embodiment of adjustable buckle members of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

As can be seen in FIG. 1, a user 10 of a respirator mask 12 is operating a piece of machinery. The respirator mask 12 includes a pair of adjustable buckles 14 located at the back of the mask.

FIG. 2 illustrates that the adjustable buckle 14 is composed of two component adjustable buckle members 16 and 18 each located at the end of a strap member 20. The buckle member 16 is formed as a single member and the buckle member 18 is formed as three identical members. As shown in FIG. 2 the adjustable buckle members 16 and 18 are molded around the strap 20 and form the end portions for the strap 20.

FIGS. 3 and 4 illustrate the adjustable buckle 14 in top and cross-sectional views. As can be seen in FIGS. 3 and 4, the strap member 20 runs continuously through adjustable buckle members 16 and 18. As explained in U.S. Pat. No. 5,970,585, the strap member 20 is parted to form the two separate adjustable buckle end members 16 and 18 shown in FIG. 2. As can also be seen in FIGS. 3 and 4 the end portion of each adjustable buckle member 18 is formed as outwardly extending wing portions 22. These wing portions 22 fit within the outwardly extending flange members 24 formed at the end of adjustable buckle member 16. The adjustable buckle 14 is thereby engaged or disengaged easily by merely slipping the wing members 22 of any of the three buckles 18 to interlock with the flange members 24. This can also be seen in the perspective view of FIG. 2. The length of the strap 20 can be adjusted in increments dependant on which on e of the three buckles is engaged with the flange 24.

FIG. 3 also shows broken way portions 25 which illustrate that the strap 20 becomes narrower in a length of the strap 26 that is located within molded channels 27 in the adjustable buckle members 16 and 18 as described in U.S. Pat. No. 5,970,585. Similarly FIG. 4 shows that the strap portion 26 is also thinner in the channels 27 which are contained within the adjustable buckle members 16 and 18. The molded channels 27 are the result of stretching the strap member 20 to be narrower and thinner while the adjustable buckle members 16 and 18 are molded around the strap member. This insures that upon cooling the strap portion 26 will be locked within the molded channels 27 formed in the molded adjustable buckle members 16 and 18.

FIG. 5 illustrates an alternate embodiment wherein the multiple buckles 18 are formed as one continuous member without the interconnecting strap portions of the continuous strap 20 as shown in FIGS. 2 and 3. The structure of FIG. 5 is shorter and it would be possible to have a greater number of adjustments in the same length as FIG. 3 by increasing the number of buckle members 18. The structure of FIG. 5 is stiffer and does not lie as comfortably against the back of the head. The structure of FIGS. 2-4 is preferred for that reason.

It will be understood that any number of buckles members 18 may be used to increase the number of adjustments and the invention is not limited to three such members. The buckle member 16 may also be increased in number to provide for additional adjustments and both buckle members 16 and 18 may be multiples so as to further increase the range of adjustments.

Although the invention has been described with reference to a particular embodiment, it should be appreciated that various adaptations and modifications may be made and the invention is only to be limited by the appended claims. 

1. An adjustable buckle located around a resilience strap for a respirator including the following: a. a resilient strap material having a particular length, width and thickness; b. an adjustable buckle molded around the strap at a particular position; c. the adjustable buckle formed of two interlocking members each member located at an end position of the strap and having at least one portion that interlocks with a corresponding portion of the other member to provide for locking and unlocking of the members with each other; d. at least one of the interlocking members including a plurality of portions that interlocks with the corresponding portion of the other member; and e. the plurality of portions that interlock with the corresponding portion of the other member are spaced from each other along the length of the strap so that an individual one of the plurality of portions may be interlocked with the corresponding portion of the other member to adjust the length of the strap.
 2. The adjustable buckle of claim 1 wherein the plurality of portions that interlock with the corresponding portion of the other member spaced from each other along the length of the strap are formed as one continuous structure molded around the strap.
 3. The adjustable buckle of claim 1 wherein the plurality of portions that interlock with the corresponding portion of the other member spaced from each other along the length of the strap are formed as discontinuous structures each molded around the strap and separated by a short section of strap material between each structure.
 4. The adjustable buckle of claim 1 wherein the plurality of portions that interlock with the corresponding portion of the other member is at least three in number.
 5. The adjustable buckle of claim 1 wherein both of the interlocking members include a plurality of portions that interlocks with the corresponding portion of the other member. 